The podcast episode of "Stuff You Should Know" focuses on the 1980 eruption of Mount St. Helens in Washington state. The hosts and their guest provide an overview of how volcanoes work, specifically strato volcanoes like Mount St. Helens. They discuss the lead up to the eruption, including the bulging of the mountain caused by pressure from the magma chamber. Despite warnings from volcanologists, some people chose to stay in the area, including Harry Truman, who became famous for his refusal to evacuate.
The major eruption occurred on March 27th, creating a new crater and sending a huge ash column into the air. The area was evacuated, but some people were allowed to return to check on their homes, leading to casualties when the eruption resumed. In total, 57 people died in the eruption. The episode also covers the aftermath of the eruption, including the devastation to the surrounding area and the natural laboratory it created for volcanologists and seismologists to study.
The hosts also briefly touch on the history of the area and the legends surrounding the mountains in the region. They mention the desire to visit a Trip Advisor-reviewed visitor center and read and discuss a listener email about the meaning behind the term "toilet" and the phrase "strangers in the beverage" from a previous episode. The email provides insight into the Scottish tradition of using tea leaves to predict the future and meet new people.
Overall, the episode provides a comprehensive overview of the 1980 eruption of Mount St. Helens, including its lead up, the eruption itself, and its aftermath. The hosts also incorporate humor and listener feedback to keep the episode engaging and informative.